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Science & Mathematics - 19 August 2007

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Agriculture · Alternative · Astronomy & Space · Biology · Botany · Chemistry · Earth Sciences & Geology · Engineering · Geography · Mathematics · Medicine · Other - Science · Physics · Weather · Zoology

both purine and pyrimidine bases are heterocyclic aliphatic ring structures - true or false?

sugars are good examples of molecules containing the amine group - true or false?

DNA, protein and ester formation always involve a condensation type of reaction - true or false?

in nucleic acids, carbon 4 of the pentose sugar is attatched to an organic nitrogenous base - true or false?

Amino acid monomers are the building blocks of polymeric DNA molecules - true or false?

Geometric (stereo) isomes exist in both cis and trans form - true or false?

All aliphatic hydrocarbons are based on the benzene molecule - true or false?

2007-08-19 06:21:30 · 1 answers · asked by Anonymous in Chemistry

0

Plz help me !!
Add 5 drops of propan-2-ol to 10 drops of sulphuric acid. Now add 2 drops of potassium dichromate solution and warm.
1.Note the smell and the color changes
2.Which reactant is oxidised in this reaction?
3.Name the organic compound formed and what homologous series does it belong to?
4.What would be the result if 2-methyl-propan-2-ol was reacted with acidified potassium dichromate ?
5.What other oxidising agents could be used for this reaction?
6.Oxidation of an alcohol produced 2-methylpropanoic acid. Name this alcohol

A lot of thanks plz help >.< !!!

2007-08-19 06:17:34 · 2 answers · asked by Yellow Flash 1 in Chemistry

I purchased a small electric incubator for my geese eggs. Every thing worked properly for a fortnight when due to a central power cut for about half an hour, all my 18 eggs in the incubator had to be thrown away. So I think I need a stand-by generator or any simple apparatus to assist the incubator; somebody advised a U.P.S currently used for computers. Please help me for any simple way to boost the incubator.

2007-08-19 06:17:15 · 3 answers · asked by dayapin39 3 in Engineering

2007-08-19 06:11:37 · 8 answers · asked by amponnu 1 in Engineering

2007-08-19 06:09:28 · 10 answers · asked by prash_dravid 1 in Parapsychology

Oxidation to carbonyl compounds and carboxylic acids:

Add 5 drops of ethanol to 10 drops of sulphuric acid. Now add 2 drops of potassium dichromate solution and warm
1. What' is the smell and color changes ?
2.The reason for the color change?
3.Why is sulphuric acid added to the reaction mixture?
4.State the oxdising agent and the final product of oxidation

Any help would be thankful ^^

2007-08-19 06:08:10 · 1 answers · asked by Ice Ice 1 in Chemistry

paint
to make the orange the shade you like you need to mix 2/3 of a bottle of red paint with each 4/5 of a bottle of yellow paint you use

you need 88 bottles of this orange paint
how many bottles of red paint will you need and how many of yellow paint will you need(all bottles are the same size)


please explain how you got the answer to win

2007-08-19 06:07:08 · 6 answers · asked by Anonymous in Mathematics

I know nothing about space dimensions so be as specific and detailed in your answers as you can be. Please.

2007-08-19 06:04:45 · 6 answers · asked by nayadeep 2 in Astronomy & Space

The pages of a textbook have uniform margins of 2 centimeters on all four sides. If the area of teh entire page is 480 square cenitmeters and the area of the printed proportion is 320 square centimeters, find the dimensions of the page.
how do you find the equation?
is it..
4(x+2)=800

2007-08-19 06:03:18 · 4 answers · asked by Anonymous in Mathematics

do not depend on education to answer this kind of questions,,

2007-08-19 06:03:09 · 8 answers · asked by hhawil 1 in Mathematics

a) 5
b) 8
c) 14
d) 33

2007-08-19 06:01:23 · 2 answers · asked by Anonymous in Mathematics

i am confused.

for many years , science taught me that earth rotate around the sun and stuff.

how do i know we are not in a merry go around situation ? a kid inside the merry go around will think everyone around her is spinning .. while people outside the mgr will think that she is the only 1 spinning.

would it make any difference if the universe is rotating around us , or like the solar system is rotating and other stars are also rotating while earth is fixed ? ?

2007-08-19 05:58:57 · 4 answers · asked by Curious 3 in Earth Sciences & Geology

I have asked for explanations and formuli and how you arrive at your solution[s].
NOT one person has worked this out--
they only indicate it sounds inefficient.
I am not interested in how something
sounds.
I am interested in scientific math;
algebra or calculus.
IF these things occurred, what would
be the scientific answer.
i gave specifics and I got back
maybe this and maybe that.
This won't work with that, period.
I need to know the why and why nots
analytically!
---
ship goes 16 kiilometers fast.
forget the size and length of the ship.
its top speed with diesel is 16.
NO other engines so far are faster.
------
it can add 3 other forms of propulsion;
sails, fans and photo cells.
if used alone they have specific
output speeds.
--
is there any combination or other
approach that will speed up the
ship [excluding jet propulsion] and
larger diesel engines?
[and keeping the weight the same].

2007-08-19 05:50:06 · 4 answers · asked by kemperk 7 in Physics

Find the area of a trapezoid with bases 21in and 37in and a height of 15in.

2007-08-19 05:49:01 · 8 answers · asked by Adrienne W 1 in Mathematics

What would be the estimated figures?

2007-08-19 05:48:15 · 1 answers · asked by Thop ite 2 in Physics

2007-08-19 05:45:57 · 4 answers · asked by Anonymous in Chemistry

Find the base of the parallelogram if the area is 120in2 and the height is 8 inches.

2007-08-19 05:40:25 · 8 answers · asked by Adrienne W 1 in Mathematics

Find the missing diagonal of a rhombus if the area is 92ft2 and the other diagonal is 8 feet.

2007-08-19 05:38:27 · 3 answers · asked by Adrienne W 1 in Mathematics

4

the answer they give is x= (e^10 - 1)/(2), but i do not know how they came to this.

2007-08-19 05:31:17 · 8 answers · asked by Anonymous in Mathematics

Basically, how much time will have passed on earth if Batman left at the speed of light for 365 earth days?

2007-08-19 05:31:04 · 10 answers · asked by PengiHogo 2 in Astronomy & Space

if any ,please tell me some of these sites.

2007-08-19 05:25:54 · 2 answers · asked by Anonymous in Engineering

Also, what constitutes the difference between classifying a species as a plant or animal (is it presence of chloroplasts, ability to move, etc?)

2007-08-19 05:24:20 · 3 answers · asked by curiousss 1 in Biology

To estimate the height of a tree,two people position themselves 25 feet aprt. From the first person, the bearing of the tree is N 48 degree E and the angle of elevation to the top of the tree is 73 degree. if the bearing of the tree from the second person is N 38 degree W, estimate the height of the tree to the nearest foot.
PLEASE SHOW ME THE FIGURE, I DON'T KNOW HOT TO DRAW IT, THAT'S MY QUESTION.

2007-08-19 05:21:17 · 4 answers · asked by Zong 2 in Mathematics

I have school starting on monday and we received a packet for summer studying if we felt neccessary a few days ago at my schools open house. Only problem is, I forgot a lot of the stuff I learned in Geometry and Algebra 2. I get good grades so I'd hate to go in there all confused. I was able to do some of the problems but not all. Here are some sample problems I need to learn how to do...

Solve the following for x:

1.) -17/8x - 4/3 = 1

2.) 51/2x - 23/3x = 6



Solve each system of equations for x and y:

1.) { 4x-3y = -6
{ x+2y = -7

2.) { 19=5x+2y
{ 1=3x-4y


Compute the products:

1.) (3x² - 2a²)²

2.) [(a+b)-4] [(a+b)+4]


Factor the following:

1.) ab-bc+a²-ac

2.) 3x² - 22x - 16



Those are just some random problems I'm having trouble with.

This is not homework, it is only a summer study packet that should get me ready for class on monday.

2007-08-19 05:14:22 · 3 answers · asked by Anonymous in Mathematics

I work in an organization that services and repairs loading bay doors, dock levellers, scissor lifts & roller shutter doors. I have recently applied for a promotion of sorts but struggle on the electrical side. Any help greatly appreciated.
Thanks

2007-08-19 05:11:08 · 5 answers · asked by mrswebber 1 in Engineering

i have made a crude potato launcher using pvc pipe, screws, 2-core speaker cable and a car battery. i have screwed two machine screws into the pipe so that the ends are very close (but not touching) and have the cable wrapped around the screws and hooked up to the battery at the other end. The idea being that i fill the pvc pipe with aerosol, turn on the battery, electrical charge travels up the cable, to the screws and jumps from one to the other, igniting the gas and launching my potato. my problem is im not getting a spark, what am i doing wrong? (the cable is touching both the pvc and the screws, would this create a problem)

2007-08-19 05:08:28 · 3 answers · asked by Anonymous in Physics

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